Jennie-Lynn Hayden, the superheroine known as Jade in the DC Comics universe, was a member of Infinity Inc.
Jade is the sister of Obsidian, who was overtly portrayed as a Catholic. The difference in their respective religious affiliations has been a plot point at least once.
Jade is a Protestant Christian. In the Infinity, Inc. comic book series, Jade's religious affiliation was not mentioned as frequently or as prominently as the Catholic religious affiliation of her twin brother, Todd Rice (a.k.a. "Obsidian"). But the series did explicitly identify Jade as a Protestant.
Although Jade and Obsidian are siblings, they were not raised in the same religious denomination. The twins were raised apart and did not even know about the existence of each other until they were in their late teens or early twenties. Similarly, Scott and Alex Summers (Cyclops and Havok of the X-Men) were siblings (although not twins), who were raised apart, one Protestant and the other Catholic.
Infinity, Inc. #5 prominently featured Obsidian praying at the pulpit of a Catholic church. In this story, Jade enters the church as well and asks the priest, who was standing near her, if she could join her brother in prayer, even though she is a Protestant. The priest naturally invited her to do so. Jade knelt beside her brother, and they both prayed for their biological father, a man who they barely knew at that time. Jade stayed by Obsidian's side when he lit a memorial candle for their father.
From: "Any Christian Superheroes?" thread began 22 April 2004 on rec.arts.comics.dc.universe newsgroup (http://groups.google.com/group/rec.arts.comics.dc.universe/browse_thread/thread/4e5839f075fecf76/8821b5db671e7ce1; viewed 20 June 2006):
From: Gustavo Wombat
Date: Thurs, Apr 22 2004 12:03 pm
I can't think of any major superheroes that strongly believe in any real faith, and that surprises me. Certainly not in the DC Universe. I think there are more minority superheroes than religious ones...
From: Dan McEwen
Date: Thurs, Apr 22 2004 7:24 pm
Obsidian was a veritfied Catholic while Jade was Protestant (but no particular denomination named). This information came out of one of the earlier issues of Infinity, Inc.
From: "What Religions are Superman and Batman?" forum discussion, started 29 January 2006 on "Sense of the Numinous" website (http://p083.ezboard.com/what-religoins-are-superman-and-Batman/fhavetheologywillarguefrm14.showMessage?topicID=136.topic; viewed 30 May 2007):
1/29/06 9:35 am
Adherents.com has a fun page on the religious affliations of superheroes...
Jade (Infinaty Inc.) (listed as merely "Protestant" but from the first Infinity, Inc. issue where she and her borther are seen praying, I would say Luthern, or Anglican because the peracher had a collar).
From: "Barry Allen is Jewish?" forum discussion, started 13 May 2005 on "Comic Bloc" website (http://www.comicbloc.com/forums/archive/index.php/t-4308.html; viewed 20 July 2007):
May 15th, 2005, 09:12 PM
I thought one of the most interesting aspects of Infinity Inc. was the way Roy Thomas portrayed the characters' various religions and how they influenced the characters lives.
Seeing the characters praying, lighting candles for loved ones, having Bar Mitzvahs, made them more human to me than characters in most other funny books ;).
Sure religion is controversial and people believe different things on both sides of the 4th wall but I find it interesting to see it having such a keen role in the lives of young people who might otherwise seem silly because they choose to run around in tights instead of trying to lead "normal" lives.
And even though I may never know what Roy Thomas' religion is, it showed me what an important role his beliefs had in his own life :).